Passenger airplanes often include emergency inflatable slides which are designed to automatically inflate upon opening of the doors when armed. The slide is contained in the door and when in the armed configuration, the base of the slide is anchored to the fuselage: opening of the door thus pulls the slide open which is then inflated with pressurized gas. In the disarmed configuration, the base of the slide is anchored to the door and follows the door upon its opening.
U.S. Pat. No. 5,738,303 shows a mechanism where a fixed jaw cooperates with a movable jaw of a linkage member. The movable jaw is pivotally attached between two flanges of a door base plate and slidingly and pivotally received in a slot of a bell crank, with the bell crank being rotated by a torque tube. The two jaws together grasp the girt bar when the mechanism is in the disarmed configuration. The mechanism is relatively complex, with movement of the jaw being determined by the interaction of multiple members.
The girt bar is usually retained adjacent the floor structure near the door opening, which is a zone prone to moisture and as such ice build up at low temperatures. Such ice build up may interfere with the operation of the mechanism between the disarmed and armed configurations and/or the movement of the girt bar in the disarmed configuration upon opening of the door.